Design and performance evaluation of a high-resolution small animal positron tomograph

The authors have used Monte Carlo simulation methods to design and evaluate a small animal positron tomograph. The tomograph has an inner diameter of 34.37 cm and a field of view of 20 cm (diameter) transaxially and 6 cm axially. The basic gamma-ray detector unit consists of a partially segmented EGO block made of 18/spl times/16 crystals of dimensions 3.35 mm/spl times/3.30 mm/spl times/30 mm, read out by a position sensitive photomultiplier tube with crossed anode wires. The design of the block was accomplished with the authors' recently developed Monte Carlo simulation program for PET design, which also was used for the evaluation of the performance of the tomograph. The rate (trues, randoms, NEC) performance as well as the resolution have been studied and compared to those of other tomographs.